Improvements in HIV treatment have dramatically reduced AIDS-related morbidity and mortality in the United States and Europe. More recently, lower drug prices and an increased focus on the global HIV epidemic has created tremendous momentum toward the development of HIV treatment programs in less developed countries in Africa, Asia and the Caribbean. With a distinguished track record of patient-oriented HIV outcomes research, Dr. Freedberg proposes to build on over 10 years of experience examining the clinical impact, cost, and cost-effectiveness of alternative HIV care strategies and to expand opportunities for junior investigators to develop skills in these areas. Research will focus in three main areas: optimal management strategies for HIV in the US, the cost-effectiveness of different strategies for HIV testing, and the impact of various strategies for antiretroviral use and opportunistic infection prophylaxis in less developed countries. This proposal has the following three specific aims: 1) To provide mentoring for young investigators in patient-oriented research in HIV disease. 2) To use ongoing multidisciplinary HIV-related modeling and outcomes research as a platform for training young investigators. 3) To utilize these efforts to address critical HIV clinical management questions in a variety of US and international settings. Using methods of clinical epidemiology, decision analysis, and simulation modeling, Dr. Freedberg proposes to expand on the past decade of work to focus added time and energy into questions at the forefront of HIV management throughout the world. By providing increased mentoring to fellows and junior faculty in the methods of outcomes research, Dr. Freedberg will create a multiplicative effect in increasing research capability in this important area of HIV-related patient-oriented investigation.